JP2016038433A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a configuration to prevent the occurrence of a domain in a liquid crystal display device of an IPS system having a pixel electrode formed of one interdigital electrode.SOLUTION: An interlayer insulating film is formed on a common electrode formed in a planar shape; a pixel electrode 112 is formed on the interlayer insulating film; the interval between a TFT substrate and an opposing substrate is regulated by a columnar spacer 30. The pixel electrode 112 includes one interdigital electrode and a contact part, and the tip of the interdigital electrode is overlapped with the columnar spacer in a plan view. Since the columnar spacer 30 is present in an area where an electric field rotating liquid crystal molecules in a reverse direction is generated when a voltage is applied to the pixel electrode 112, reverse rotation of the liquid crystal molecules does not occur and the occurrence of a domain can be prevented.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a display device, and more particularly to a horizontal electric field drive type liquid crystal display device having a high-definition screen.

  In a liquid crystal display device, a TFT substrate in which pixels having pixel electrodes and thin film transistors (TFTs) are formed in a matrix and a counter substrate are arranged opposite the TFT substrate, and liquid crystal is sandwiched between the TFT substrate and the counter substrate. ing. An image is formed by controlling the light transmittance of the liquid crystal molecules for each pixel. Since liquid crystal display devices are flat and lightweight, they are used in various fields. Small liquid crystal display devices are widely used for mobile phones, DSCs (Digital Still Cameras), and the like.

  In a liquid crystal display device, it is necessary to define the distance between the TFT substrate and the counter substrate, but this distance is defined by forming a columnar spacer on the counter substrate or the TFT substrate to maintain high accuracy of the distance. Can do. In Patent Document 1, a columnar spacer is formed on the counter substrate side, and this columnar spacer is brought into contact with a portion where the TFT on the TFT substrate side is formed, that is, an end portion of the pixel. A configuration for maintaining the above is described.

JP 2012-108541 A

  A viewing angle characteristic is a problem in a liquid crystal display device. The viewing angle characteristic is a phenomenon in which luminance changes or chromaticity changes when the screen is viewed from the front and when viewed from an oblique direction. The viewing angle characteristic is excellent in an IPS (In Plane Switching) system in which liquid crystal molecules are operated by a horizontal electric field.

  There are various types of IPS systems. For example, a common electrode is formed with a flat solid surface, and a comb-like pixel electrode is disposed on the common electrode, and an electric field generated between the pixel electrode and the common electrode is used. The method of rotating liquid crystal molecules is currently mainstream because the transmittance can be relatively increased. On the other hand, when the screen becomes high definition, the area of the pixel also decreases, so that only one comb-shaped electrode constituting the pixel electrode can exist.

  In the IPS system, when there are regions in the pixel in which the liquid crystal molecules rotate in different directions, a so-called domain is generated at the boundary between the region in which the liquid crystal rotates in the forward direction and the region in which the liquid crystal rotates in the reverse direction. In the domain, light leakage or light scattering occurs during black display, and light does not transmit during white display. This domain generally has a streak-like portion having a low transmittance or a portion having a high transmittance, and adversely affects the brightness and contrast of the screen.

  An object of the present invention is to suppress the occurrence of a domain when the number of comb-teeth electrodes of a pixel electrode is one in an IPS liquid crystal display device.

  The present invention overcomes the above-mentioned problems, and main specific means are as follows.

  (1) A liquid crystal display device in which pixels having pixel electrodes and TFTs are formed in a matrix and a liquid crystal is sandwiched between a counter substrate, and the pixel includes a planar electrode on a common electrode An interlayer insulating film is formed, and a pixel electrode is formed thereon. A distance between the TFT substrate and the counter substrate is defined by a columnar spacer, and the pixel electrode has one comb-like electrode and a contact portion. The tip of the comb-like electrode overlaps with the columnar spacer when seen in a plan view.

  (2) The liquid crystal display device according to (1), wherein the tip of the comb-like electrode of the pixel electrode is bent and the width is gradually narrowed toward the end.

  (3) A liquid crystal display device in which pixels having pixel electrodes and TFTs are formed in a matrix and a liquid crystal is sandwiched between a counter substrate and the pixel has a flat electrode on a common electrode An interlayer insulating film is formed, and a pixel electrode is formed thereon. A distance between the TFT substrate and the counter substrate is defined by a columnar spacer, and the pixel electrode has one comb-like electrode and a contact portion. The liquid crystal display device is characterized in that the contact portion of the comb-like electrode overlaps with the columnar spacer in a plan view.

  (4) The liquid crystal display device according to (3), wherein a base of the comb-like electrode with respect to the contact portion overlaps with the columnar spacer as viewed in a plan view.

(5) The contact portion has a corner portion, and the corner portion is
The liquid crystal display device according to (3), wherein the liquid crystal display device overlaps with the columnar spacer as viewed in a plane.

  (6) A liquid crystal display device in which pixels having pixel electrodes and TFTs are formed in a matrix and a liquid crystal is sandwiched between a counter substrate, wherein the pixels are formed on the pixel electrodes formed in a planar shape. An interlayer insulating film is formed, and a common electrode having a slit is formed thereon, a distance between the TFT substrate and the counter substrate is defined by a columnar spacer, and a tip of the slit of the common electrode is seen in a plan view A liquid crystal display device which overlaps with the columnar spacer.

  (7) The liquid crystal display device according to (6), wherein a tip of the slit of the common electrode is bent, and the width gradually decreases toward the end.

It is sectional drawing of the liquid crystal display device with which this invention is applied. 3 is a perspective plan view of a pixel according to Embodiment 1. FIG. It is a top view which shows the shape of a pixel electrode. It is a top view which shows the rotation direction of the liquid crystal molecule in the conventional pixel electrode. It is a top view which shows operation | movement of the pixel electrode which prevented the reverse rotation of the liquid crystal molecule. It is a top view which shows the rotation direction of the liquid crystal molecule in an actual pixel electrode. It is a top view which shows rotation of the liquid crystal molecule in the vicinity of the front-end | tip of the pixel electrode by this invention. 6 is a perspective plan view of a pixel according to Embodiment 2. FIG. It is a top view which shows the relationship between the position of the pixel electrode in FIG. 8, and a columnar spacer. FIG. 10 is a plan view showing the relationship between the positions of pixel electrodes and columnar spacers in another aspect of Example 2;

  Before describing a specific pixel structure according to the present invention, a structure of a liquid crystal display device to which the present invention is applied will be described. FIG. 1 is a cross-sectional view of a liquid crystal display device to which the present invention is applied. The TFT in FIG. 1 is a so-called top gate type TFT, and LTPS (Low Temperature Poly-Si) is used as a semiconductor to be used. On the other hand, when an a-Si semiconductor is used, a so-called bottom gate type TFT is often used. In the following description, a case where a top gate type TFT is used will be described as an example. However, the present invention can also be applied to a case where a bottom gate type TFT is used.

In FIG. 1, a first base film 101 made of SiN and a second base film 102 made of SiO ₂ are formed on a glass substrate 100 by CVD (Chemical Vapor Deposition). The role of the first base film 101 and the second base film 102 is to prevent impurities from the glass substrate 100 from contaminating the semiconductor layer 103.

  A semiconductor layer 103 is formed on the second base film 102. The semiconductor layer 103 is obtained by forming an a-Si film on the second base film 102 by CVD, and converting it into a poly-Si film by laser annealing. The poly-Si film is patterned by photolithography.

A gate insulating film 104 is formed on the semiconductor layer 103. This gate insulating film 104 is a SiO ₂ film made of TEOS (tetraethoxysilane). This film is also formed by CVD. A gate electrode 105 is formed thereon. The gate electrode 105 also serves as the scanning line 10 shown in FIG. For example, the gate electrode 105 is formed of a MoW film. When it is necessary to reduce the resistance of the gate electrode 105 or the scanning line 10, an Al alloy is used.

  The gate electrode 105 is patterned by photolithography. During this patterning, impurities such as phosphorus or boron are doped into the poly-Si layer by ion implantation to form the source S or drain D in the poly-Si layer. To do. Further, an LDD (Lightly Doped Drain) layer is formed between the channel layer of the poly-Si layer and the source S or the drain D using a photoresist when patterning the gate electrode 105.

Thereafter, a first interlayer insulating film 106 is formed of SiO _{2 so as} to cover the gate electrode 105. The first interlayer insulating film 106 is for insulating the gate wiring 105 and the contact electrode 107. A through hole 120 for connecting the source portion S of the semiconductor layer 103 to the contact electrode 107 is formed in the first interlayer insulating film 106 and the gate insulating film 104. Photolithography for forming the through hole 120 in the first interlayer insulating film 106 and the gate insulating film 104 is performed simultaneously.

  A contact electrode 107 is formed on the first interlayer insulating film 106. The contact electrode 107 is connected to the pixel electrode 112 through the through hole 130. The drain D of the TFT is connected to the video signal line 20 shown in FIG.

  The contact electrode 107 and the video signal line are formed in the same layer at the same time. For the contact electrode 107 and the video signal line (hereinafter represented by the contact electrode 107), for example, an AlSi alloy is used to reduce the resistance. Since the AlSi alloy generates hillocks or Al diffuses to other layers, for example, a structure is adopted in which AlSi is sandwiched between a barrier layer made of MoW (not shown) and a cap layer.

  An inorganic passivation film (insulating film) 108 is formed covering the contact electrode 107 to protect the entire TFT. The inorganic passivation film 108 is formed by CVD in the same manner as the first base film 101. An organic passivation film 109 is formed so as to cover the inorganic passivation film 108. The organic passivation film 109 is made of a photosensitive acrylic resin. The organic passivation film 109 can be formed of silicone resin, epoxy resin, polyimide resin, or the like in addition to acrylic resin. Since the organic passivation film 109 has a role as a planarizing film, it is formed thick. The thickness of the organic passivation film 109 is 1 to 4 μm, but in many cases is about 2 μm.

  In order to establish conduction between the pixel electrode 110 and the contact electrode 107, a through hole 130 is formed in the inorganic passivation film 108 and the organic passivation film 109. The organic passivation film 109 uses a photosensitive resin. When this resin is exposed after application of a photosensitive resin, only the portion exposed to light is dissolved in a specific developer. That is, the formation of a photoresist can be omitted by using a photosensitive resin. After the through-hole 130 is formed in the organic passivation film 109, the organic passivation film 109 is completed by baking the organic passivation film at about 230 ° C.

  Thereafter, ITO (Indium Tin Oxide) to be the common electrode 110 is formed by sputtering and patterned so as to remove the ITO from the through hole 130 and its periphery. The common electrode 110 can be formed in a planar shape common to each pixel. Thereafter, SiN to be the second interlayer insulating film 111 is formed on the entire surface by CVD. Thereafter, a through hole is formed in the second interlayer insulating film 111 and the inorganic passivation film 108 in order to make the contact electrode 107 and the pixel electrode 112 conductive in the through hole 130. Thereafter, ITO is formed by sputtering and patterned to form the pixel electrode 112. FIG. 2 and subsequent figures show the planar shape of the pixel electrode 112 in the present invention.

  Columnar spacers 30 are formed on the second interlayer insulating film 111. Note that the columnar spacer 30 covers a part of the pixel electrode 112. The columnar spacer 30 can be formed of the same material as the organic passivation film 109. An organic material is formed to a thickness corresponding to the distance between the TFT substrate 100 and the counter electrode 200 and dried, and then unnecessary portions are removed by photolithography and baked to form the columnar spacers 30. In FIG. 1, the columnar spacer 30 overlaps with a part of the pixel electrode 112. By overlapping the columnar spacer 30 with the pixel electrode 112, the reverse rotation of the liquid crystal molecules 301 in this portion is prevented, and the occurrence of domains is prevented.

  In FIG. 1, the columnar spacer 30 is formed on the TFT substrate 100 side, but may be formed on the counter substrate 200 side. However, since the columnar spacer 30 is superimposed only on a specific portion of the pixel electrode 112, the positional accuracy of the columnar spacer 30 is important. If the columnar spacer 30 is formed on the TFT substrate 100 side, the position with the pixel electrode 112 can be determined by the accuracy of mask alignment. On the other hand, when the columnar spacer 30 is formed on the counter substrate 200 side, the positions of the columnar spacer 30 and the pixel electrode 112 depend on the alignment accuracy of the TFT substrate 100 and the counter substrate 200. If the spacer 30 is formed, the columnar spacer 30 and the pixel electrode 112 can be aligned with higher accuracy.

  An alignment film material is applied onto the pixel electrodes 112, the interlayer insulating film 111, and the columnar spacers 30 by flexographic printing, ink jet, or the like, and baked to form the alignment film 113. The alignment film 112 is formed to cover the interlayer insulating film 111, the pixel electrode 112, and the columnar spacer 30. However, since the columnar spacer 30 has a height, the alignment film 113 on the columnar spacer 30 is very thin due to leveling. It has become. For the alignment treatment of the alignment film 113, photo-alignment using polarized ultraviolet rays is used in addition to the rubbing method.

  When a voltage is applied between the pixel electrode 112 and the common electrode 110, electric lines of force as shown in FIG. 1 are generated. The liquid crystal molecules 301 are rotated by this electric field, and an image is formed by controlling the amount of light passing through the liquid crystal layer 300 for each pixel.

  In FIG. 1, a counter substrate 200 is disposed with a liquid crystal layer 300 interposed therebetween. A color filter 201 is formed inside the counter substrate 200. The color filter 201 is formed with red, green, and blue color filters for each pixel, thereby forming a color image. A black matrix 202 is formed between the color filters 201 to improve the contrast of the image.

  Note that the black matrix 202 also has a role as a light shielding film of the TFT, and prevents a photocurrent from flowing through the TFT. Further, since the alignment of the liquid crystal is disturbed in the vicinity of the columnar spacer 30, the black matrix 202 also has a role of preventing light leakage at this portion.

  An overcoat film 203 is formed to cover the color filter 201 and the black matrix 202. Since the surface of the color filter 201 and the black matrix 202 is uneven, the surface is flattened by the overcoat film 203. On the overcoat film 203, an alignment film 113 for determining the initial alignment of the liquid crystal is formed. For the alignment treatment of the alignment film 113, a rubbing method or a photo-alignment method is used in the same manner as the alignment film 113 on the TFT substrate 100 side. When the columnar spacer 30 is formed on the counter substrate 200 side, it is formed on the overcoat film 203.

  The above configuration is an example. For example, the inorganic passivation film 108 on the TFT substrate 100 may not be formed depending on the type. In addition, the formation process of the through hole 130 may differ depending on the type. Hereinafter, the present invention will be described in detail using examples.

  FIG. 2 is a perspective plan view of the pixel portion showing Embodiment 1 of the present invention. A pixel electrode 112 is formed in a region surrounded by the scanning line 10 and the video signal line 20. The pixel electrode 112 is a single comb-like electrode. When the pixel width is reduced, a plurality of comb-like electrodes cannot be arranged in the pixel.

  In FIG. 2, a semiconductor layer 103 is formed between the video signal line 20 and the pixel electrode 112. The semiconductor layer 103 is connected to the video signal line 20 via the through hole 140 and is connected to the contact electrode 107 via the through hole 120. The semiconductor layer 103 extends in a U shape between the through hole 120 and the through hole 140 and passes under the scanning line 10 twice. In FIG. 2, since the scanning line 10 serves as the gate electrode 105, the TFT is a double gate. The position of each electrode or wiring in the cross-sectional direction is as described in FIG.

  The major axis of the pixel electrode 112 is a direction perpendicular to the scanning line 10, that is, the extending direction of the video signal line 20. As shown in FIG. 2, the alignment direction AL of the alignment film 113 is inclined at a predetermined angle with respect to the extending direction of the video signal line 20. This angle is 5 to 20 degrees. This is for defining the rotation direction of the liquid crystal molecules 301 by the electric field. At the tip of the pixel electrode 112, the rotation direction of the liquid crystal molecules 301 becomes unstable and a domain is generated. To prevent this, the tip of the pixel electrode 112 is bent and gradually becomes narrower toward the end. ing.

  The pixel electrode 112 is connected to the contact electrode 107 through the through hole 130 and receives a video signal supplied through the TFT. Since the through hole 130 is formed to be large, the contact portion 1121 of the pixel electrode 112 is formed widely in order to provide a sufficient connection region between the pixel electrode 112 and the contact electrode 107.

  In FIG. 2, columnar spacers 30 are formed at the intersections of the scanning lines 10 and the video signal lines 20. Further, the tip of the pixel electrode 112 extends to the vicinity of the video signal line 20 and overlaps with the columnar spacer 30 when seen in a plan view. As a result, no liquid crystal exists in a region near the tip of the pixel electrode 112 where the liquid crystal molecules 301 are likely to reversely rotate, so that the generation of domains can be suppressed.

  FIG. 3 is a plan view showing the shape of the pixel electrode 112. In FIG. 3, the pixel electrode 112 is formed of one comb electrode and a contact portion 1121. The width pw of the comb electrode is 2 to 4 μm. The contact portion 1121 is wide in order to accommodate the through hole 130. The contact portion has a shoulder portion 1122 at the corner portion, and a portion where the comb electrode is connected to the contact portion 1121 is a root portion 1123. Shoulder 1122 may be referred to as corner 1122. The tip of the pixel electrode 112 is bent and has a triangular tip in order to prevent the occurrence of a domain. The relationship between domain generation and pixel electrodes and the configuration of the present invention will be described below.

  FIG. 4 is a plan view showing the alignment of the liquid crystal when the pixel electrode 112 is simply rectangular without a bent portion or a triangular shape with a sharp tip. In FIG. 4, a common electrode is present below the pixel electrode 112 in a planar shape via an interlayer insulating film. When a voltage is applied to the pixel electrode 112, an electric field as indicated by an arrow E is generated between the common electrode and the common electrode as viewed in a plane. On the other hand, since the liquid crystal molecules 301 are initially oriented in the AL direction, when a voltage is applied to the pixel electrode 112, the liquid crystal molecules 301 rotate as indicated by arrows. When the liquid crystal molecules 301 have positive dielectric anisotropy, the liquid crystal molecules 301 are reoriented so that the major axes of the liquid crystal molecules 301 are aligned with the direction of the electric field. The direction of rotation of the liquid crystal molecules 301 is related to the generation of domains. When the liquid crystal molecules 301 have negative dielectric anisotropy, the liquid crystal molecules 301 are reoriented so that the minor axes of the liquid crystal molecules 301 are aligned with the direction of the electric field. Since the concept is the same, hereinafter, the liquid crystal molecules will be described as having positive dielectric anisotropy.

  In FIG. 4, the liquid crystal molecules 301 close to the long side of the pixel electrode 112 rotate clockwise as indicated by an arrow when a voltage is applied to the pixel electrode 112. In both the right and left sides of the pixel electrode 112, the liquid crystal molecules 301 rotate clockwise. On the other hand, the liquid crystal molecules near the short side of the pixel electrode 112 rotate counterclockwise when a voltage is applied to the pixel electrode 112. Then, in the vicinity of the boundary between the long side and the short side of the pixel electrode 112, a domain that is a region where the rotation directions of the liquid crystal molecules 301 are opposite to each other is generated, and the image quality is deteriorated.

  FIG. 5 shows a shape in which the tip of the pixel electrode 112 is bent and sharpened in a triangular shape in order to prevent a domain. Also in the tip portion of the pixel electrode 112 in FIG. 5, the direction in which the liquid crystal molecules 301 are reoriented by the electric field is clockwise as indicated by an arrow. Therefore, with the shape of FIG. 5, the occurrence of domains can be suppressed even at the tip of the pixel electrode 112.

  However, FIG. 5 shows a case where the pixel electrode 112 can be ideally patterned. Actually, after patterning, the tip of the pixel electrode 112 is rounded and rounded as shown in FIG. In FIG. 6, the electric field at the tip of the pixel electrode 112 is generated in a direction perpendicular to the tangent line of the pixel electrode 112. In this portion, as shown in FIG. 6, an electric field is generated that rotates the liquid crystal molecules 301 counterclockwise. On the other hand, in a portion other than the tip of the pixel electrode 112, the liquid crystal molecules 301 rotate clockwise, so that a domain is generated near the tip of the pixel electrode 112. The domain range generated in the pixel electrode 112 in FIG. 6 is smaller than the domain range generated in the pixel electrode 112 in FIG. However, since the domain affects the alignment of the surrounding liquid crystal, the domain influence covers a wider range than the region where the direction of the electric field becomes irregular.

  In the present invention, as shown in FIG. 7, the columnar spacer 30 is seen in a plan view, overlapped with the tip of the pixel electrode 112, and the liquid crystal molecules 301 do not exist in the region where the liquid crystal molecules 301 are reversely rotated. Prevents the occurrence of a domain.

  In FIG. 7, the presence of the columnar spacer 30 may disturb the initial alignment of the liquid crystal molecules 301, thereby affecting the direction of rotation of the liquid crystal molecules, but this effect is slight. FIG. 7 shows a case where the plane of the columnar spacer 30 is a circle, but other shapes may be used. In this case, it is necessary to determine the planar shape of the columnar spacer 30 based on the balance between the initial alignment of the liquid crystal molecules 301 due to the presence of the columnar spacers 30 and the rotation direction of the liquid crystal molecules 301.

  As described above, according to the present embodiment, since the tip end portion of the pixel electrode 112 overlaps the columnar spacer 30, there is almost no liquid crystal molecule that rotates in the reverse direction. Even with high definition, a high-quality liquid crystal display device can be realized.

  FIG. 8 is a plan view of a pixel portion showing a second embodiment of the present invention. The feature of FIG. 8 is that the contact portion 1121 of the pixel electrode 112 overlaps the columnar spacer 30 when viewed in plan. As a result, the occurrence of a domain in the vicinity of the contact portion 1121 of the pixel electrode 112 can be prevented. The other configurations in FIG. 8 are the same as those in FIG. 2 of the first embodiment.

  FIG. 9 is a plan view showing the relationship between the pixel electrode 112 and the columnar spacer 30 in this embodiment. In FIG. 9, the vicinity of the root 1123 of the pixel electrode 112 with respect to the contact portion of the comb electrode overlaps with the columnar spacer 30 when seen in a plan view. In the vicinity of the root 1123, there is a region where the liquid crystal molecules 301 rotate counterclockwise. Therefore, by disposing the columnar spacer 30 in this region, the liquid crystal molecules 301 are excluded from this region, and the liquid crystal molecules 301 that rotate in the reverse direction. Is greatly reduced. In FIG. 9, the right shoulder of the pixel electrode 112 is inclined so that it is difficult for reverse rotation of the liquid crystal to occur.

  FIG. 10 is a plan view showing another form of the relationship between the pixel electrode 112 and the columnar spacer 30 in the present embodiment. In FIG. 10, a comb electrode base 1123 of the pixel electrode 112 and a corner portion 1122 of the contact portion 1121 are configured to overlap the columnar spacer 30 when seen in a plan view.

  In FIG. 10, the initial alignment direction of the liquid crystal molecules 301 is indicated by an arrow AL. However, when the initial alignment is such a direction, a domain is likely to be generated near the contact portion 1121 on the left side of the pixel electrode 112. In this embodiment, when viewed in a plan view, the columnar spacers 30 are arranged so as to overlap with the vicinity of the shoulder portion 1122 and the base portion 1123 of the contact portion of the pixel electrode 112, thereby eliminating the liquid crystal molecules 301 in this region. Is prevented.

  As described above, according to this embodiment, since the generation of domains in the vicinity of the contact portion of the pixel electrode can be suppressed, a high-quality liquid crystal display device can be realized even when the resolution is high.

By using both the configuration of the first embodiment and the configuration of the second embodiment, it is possible to suppress both domain generation at the tip portion of the pixel electrode and domain generation near the contact portion of the pixel electrode. However, if the columnar spacer is overlapped with the pixel electrode when seen in a plane, the transmittance of the pixel is reduced. Therefore, the range in which the columnar spacer is overlapped with the pixel electrode is determined by the balance between the transmittance and the contrast. Note that the columnar spacer may be formed on the TFT substrate side or on the counter substrate side.
In the above description, the present invention has been described with respect to the configuration in which the pixel electrode having the comb electrode is disposed on the planar common electrode via the interlayer insulating film. However, the same operation can be performed when a common electrode having a slit is formed on a planar pixel electrode through an interlayer insulating film. In this case, as for the slits formed in the common electrode, if the pixel size is reduced, only one slit can be formed per pixel.

  In this case, the present invention can be applied to the slit formed in the upper common electrode by adopting the configuration shown in the first embodiment. That is, the tip of the slit of the common electrode in the pixel is bent, and the width is narrowed as the end is approached. Then, the rotation of the liquid crystal molecules in the vicinity of the slit tip of the common electrode can be suppressed by overlapping the column tip spacer with the columnar spacer as viewed from the top.

  Even if the tip of the pixel electrode or the slit of the common electrode is designed to be a triangular shape, the actual shape is rounded as shown in FIG. That is, the actual pixel electrode or the slit of the common electrode has a configuration in which the tip gradually becomes thinner toward the end.

  Further, in the drawings in the above description, the plane of the columnar spacer is assumed to be a circle, but the plane shape of the columnar spacer may be rectangular as long as it is a plane shape that does not cause reverse rotation with respect to the liquid crystal molecules. An ellipse may be used. In the above description, the pixel electrode has a configuration in which the tip is bent and gradually decreases toward the end, but the tip shape of the pixel electrode is not limited to this shape. However, if the tip of the pixel electrode has a shape in which it is difficult for a domain to occur, the overlapping area between the columnar spacer and the pixel electrode can be reduced, so that the luminance is reduced due to the presence of the columnar spacer in the pixel. Can be prevented. The same applies to the shape of the slit formed in the common electrode.

  DESCRIPTION OF SYMBOLS 10 ... Scanning line, 20 ... Video signal line, 30 ... Columnar spacer, 100 ... TFT substrate, 101 ... 1st base film, 102 ... 2nd base film, 103 ... Semiconductor layer, 104 ... Gate insulating film, 105 ... Gate electrode 106: first interlayer insulating film, 107: contact electrode, 108: inorganic passivation film, 109: organic passivation film, 110: common electrode, 111: second interlayer insulating film, 112: pixel electrode, 113: alignment film, 120 DESCRIPTION OF SYMBOLS 1st through hole, 130 ... 2nd through hole, 140 ... 3rd through hole, 200 ... Opposite substrate, 201 ... Color filter, 202 ... Black matrix, 203 ... Overcoat film, 300 ... Liquid crystal layer, 301 ... Liquid crystal molecule 1121... Pixel electrode contact portion 1122. Over unit, 1123 ... comb electrodes root, AL ... orientation, D ... drain unit, S ... source unit

Claims (7)

A liquid crystal display device in which pixels having pixel electrodes and TFTs are formed in a matrix and liquid crystal is sandwiched between a counter substrate,
In the pixel, an interlayer insulating film is formed on a common electrode formed in a planar shape, and a pixel electrode is formed thereon,
The distance between the TFT substrate and the counter substrate is defined by a columnar spacer,
The pixel electrode has one comb-like electrode and a contact portion, and the tip of the comb-like electrode overlaps with the columnar spacer when seen in a plan view.   The liquid crystal display device according to claim 1, wherein a tip of the comb-like electrode of the pixel electrode is bent and a width gradually decreases toward an end portion. A liquid crystal display device in which pixels having pixel electrodes and TFTs are formed in a matrix and liquid crystal is sandwiched between a counter substrate,
In the pixel, an interlayer insulating film is formed on a common electrode formed in a planar shape, and a pixel electrode is formed thereon,
The distance between the TFT substrate and the counter substrate is defined by a columnar spacer,
The pixel electrode has one comb-like electrode and a contact portion, and the contact portion of the comb-like electrode overlaps with the columnar spacer when seen in a plan view. apparatus.   The liquid crystal display device according to claim 3, wherein a base of the comb-like electrode with respect to the contact portion overlaps with the columnar spacer when seen in a plan view.   The liquid crystal display device according to claim 3, wherein the contact portion has a corner portion, and the corner portion overlaps with the columnar spacer when seen in a plan view. A liquid crystal display device in which pixels having pixel electrodes and TFTs are formed in a matrix and liquid crystal is sandwiched between a counter substrate,
In the pixel, an interlayer insulating film is formed on a pixel electrode formed in a planar shape, and a common electrode having a slit is formed thereon,
The distance between the TFT substrate and the counter substrate is defined by a columnar spacer,
The liquid crystal display device, wherein a tip of the slit of the common electrode overlaps with the columnar spacer when seen in a plan view.   The liquid crystal display device according to claim 6, wherein a tip of the slit of the common electrode is bent, and the width gradually decreases toward the end.

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